What ventilation systems are required for all gasoline-powered vessels built after 1940?

For gasoline-powered vessels built after 1940, active and passive ventilation systems are required to ensure safety on board. These ventilation systems work together to reduce the risk of fuel vapors accumulating inside the engine compartment and other enclosed spaces.

Active ventilation systems typically involve powered fans that actively draw air into the vessel's compartments or expel it out, thereby promoting air circulation and preventing the buildup of dangerous fumes. On the other hand, passive ventilation systems rely on design features such as air vents and openings that allow for natural airflow without mechanical assistance.

The combination of both types of ventilation is essential for maintaining a safe environment, as it significantly lowers the risk of fire or explosion caused by flammable vapors. Proper ventilation is a critical safety consideration, especially in boats where fuel and ignition sources may be present.